The present invention relates to a mechanical horological movement.
Generally, mechanical horological movements notably comprise a barrel which houses a motor spring, a wheelwork driven by the barrel, a regulating device such as a sprung balance, and between the wheelwork and the regulating device an escapement for maintaining the oscillations of the regulating device. The arbors of certain wheels of the wheelwork bear indicator hands. The escapement comprises an escape wheel driven by the wheelwork as well as an element such as an anchor situated between the escape wheel and the regulating device.
The horological movements that currently exist on the market usually have a regulating device oscillating at a frequency of 4 Hz and an escape wheel having 20 teeth. There has also been commercialized under the trademark Zenith El Primero a movement whose regulating device oscillates at a frequency of 5 Hz and whose escape wheel to applicant's knowledge has 21 teeth.
It is known in the horological field that the higher the frequency of the regulating device the more precise time measurement is. However, an increase in frequency causes an increase in the angular speed of rotation of the escape wheel thus necessitating a modification of the wheelwork and more precisely of the gear ratios so that the indicator hands turn at the right speed. An Increase in the speed of rotation of the escape wheel has the further effect of reducing the power reserve, since the motor spring will then be released more rapidly.